Story highlights

Netanyahu has expressed skepticism about the Iranian president's intentions

Israeli Prime Minister Benjamin Netanyahu says he would take a phone call from Iran's president, if he called, but warns that he would have tough words for the man he described this week as "a wolf in sheep's clothing."

"We're not averse to calling," Netanyahu said in an interview Thursday with CNN's Piers Morgan in New York.

Western leaders have expressed optimism about Iran's more conciliatory tone under Rouhani, whose comments in recent weeks have raised hopes that a deal could be struck over the country's controversial nuclear program.

"They don't have enrichment because enrichment -- uranium enrichment -- is how you make nuclear weapons," he said in the interview, which will air at 9 p.m. ET on Friday.

Iran has repeatedly insisted that its nuclear program is for peaceful purposes.

Khodadad Seifi, an Iranian representative at the United Nations, said this week that Tehran is cooperating with the U.N.'s nuclear watchdog, the International Atomic Energy Agency, and that its work is carried out under surveillance cameras.

Unperturbed by U.S. shutdown

Asked if he was concerned about the partial shutdown of the U.S. federal government this week, Netanyahu seemed unfazed.

"They'll work it out," he said. "Been there, done that."

And despite the crisis in Washington that has paralyzed many public services, Netanyahu defended the U.S. democratic system.

"I think, with all its flaws, the American political system has a lot riding for it," he said. "It's probably the best political system in the world."